* Material: High Speed Steel 4341 Manufactured from High Speed Steel (HSS). high hardness and rust resistance for long life. * Size: M3x0.5. M4x0.7. M5x0.8. M6x1. M8x1.25. M10x1.5. 6 set sizes. that perfectly meet your different needs. hardened drill induction. resistant to slightly induced wear. to ensure the puncture speed. improve the efficiency of work. * The complete drilling. tapping. deburring and milling in one operation saves processing steps and time costs. to improve working efficiency. * 6 steel bits. suitable for wood drilling. plastic. fine copper. aluminum and other soft metals (5-6 mm). not for hard materials (eg sheet steel). * When drilling a hole. you need to inject water at the same time to cool the drill bit. This will help you increase the value of the exercises. If you can't cool the drill bit when you drill holes. the drilling speed should not be too high and you should not drill too frequently.